isCOBOL Evolve : User Interface : Controls Reference : WINDOW : Styles : { Permanent | Temporary }
{ Permanent | Temporary }
Permanent
A control with this style applied can be destroyed only by using the DESTROY statement or when the parent window is destroyed. A permanent control is more efficient than a "temporary" one since it is not created each time a DISPLAY statement is executed. This style is set by default.
Temporary
Temporary controls are destroyed when a DESTROY statement is executed, when the parent window is destroyed, when another control is created in its same position, or when a Screen Section containing a BLANK SCREEN keyword is displayed. Temporary controls are less efficient than "permanent" ones since they are created each time a DISPLAY statement is executed.
 
Example - Display a window with temporary style
working-storage section.
77 window-handle1 usage handle of window.
...
procedure division.
...
  display floating  window background-low
          size 37.3
          lines 34.2
          line 20
          column 1
          cell width 10
          cell height 10
          label-offset 20
          control font Default-Font
          color 257
          modeless
          system menu
          title-bar
          temporary
          title "Screen"
          handle window-handle1
          .